The present invention relates in general to lined high temperature conduits and, in particular, to a new and useful high temperature lined conduit, including lined elbows and tees, which permit the thermal expansion of a liner with respect to an outer covering of the conduit, elbows and tees. The invention is also drawn to a method of fabricating the conduits, elbows and tees.
It is known to utilize lined conduits for conducting high temperature media such as hot combustion gases and the like. Such conduits include an inner lining for coming into direct contact with the high temperature medium which is surrounded by an outer pipe. A space defined between the inner lining and the outer pipe is filled with castable insulating and refractory material. A basic defect in these prior art conduits are that, due to the large difference in the coefficient of expansion between the lining and the castable material, the lining expands and often collapses and becomes distorted due to its contact with the castable material which is a hard brick-like substance.